The present invention relates to an aqueous dental glass ionomer composition comprising(A) a reactive particulate glass,(B) a water-soluble, polymerizable polymer comprising acidic groups, which is reactive with the particulate glass in a cement reaction, whereby the polymerizable polymer has a polymer backbone and hydrolysis-stable pendant groups having one or more polymerizable carbon-carbon double bonds, wherein the polymerizable polymer is obtainable by a process comprising a) a step of copolymerizing a mixture comprising (i) a first copolymerizable monomer comprising at least one optionally protected carboxylic acid group and a first polymerizable organic moiety, and(ii) a second copolymerizable monomer comprising one or more optionally protected primary and/or secondary amino groups and a second polymerizable organic moiety,for obtaining an amino group containing copolymer；b) a step of coupling to the amino group containing copolymer a compound having a polymerizable moiety and a functional group reactive with an amino group of repeating units derived from the second copolymerizable monomer in the amino group containing copolymer obtained in the first step, wherein the optionally protected amino group is deprotected, so that polymerizable pendant groups are linked to the backbone by hydrolysis-stable linking groups,and, optionally, a step of deprotecting the protected carboxylic acid group after step a) or step b), for obtaining a polymerizable polymer；(C) a hydrolysis-stable, water-soluble monomer having one polymerizable double bond and optionally a carboxylic acid group, said monomer having a molecular weight of at most 200 Da；(D) a polymerization initiator system； and(E) a polymerizable hydrolysis-stable crosslinker having at least two polymerizable carbon-carbon double bonds.
